This invention relates in general to apparatuses for forming and/or maintaining a hole or cavity in a medium which would otherwise close the hole or cavity, for example: apparatuses for maintaining fishing holes cut through ice covering a body of water, and apparatuses for forming holes in concrete and other solidifying liquids or mixtures, and in compactible materials such as soil fill.
As used herein the terms "hole" and "cavity" refer to voids of any cross-section, and not necessarily of circular cross-section, and the term "hole" encompasses cavities.
While this invention can be used for a wide variety of applications to form and maintain a hole, it is particularly useful in maintaining ice fishing holes which are holes made through ice covering bodies of water for the purpose of fishing. Holes are made through the ice in many ways but the most common is by means of an auger. A typical hole is a seven inch round hole through relatively thick ice, thick enough to support fishermen and fishing shelters. Many fishermen move ice houses onto the ice for shelter from which they fish through a hole in the ice cut through a cut-out in the floor of the ice house. Making holes through such thick ice is hard work and takes a lot of time from the otherwise more enjoyable task of catching fish. The problem with holes cut in ice is that they tend to freeze over again when left inactive for some period of time, and a fisherman returning after the period of time must re-open the hole before he or she can resume fishing. Holes can be reopened by the use of power augers, power chisels and chain saws but these are all specialized and expensive equipment.
There have been ways devised to keep ice holes from freezing over. One way is to put a pail or bucket in the hole. However, this requires weights to be added to overcome the buoyancy in order to keep the pail or bucket in the hole. A larger diameter hole is also required and the ice may freeze much thicker than the pail or bucket which means that work is still necessary to make the hole go through the ice. Also, a pail or bucket is extremely difficult to remove from the ice. There are also some elaborate methods using inflatable bladders which when maintained under pressure will seal the hole. These devices require a source of pressure and if left for long periods may leak or otherwise lose their pressure which will allow the hole to freeze over the deflated bladder making it impossible to remove without cutting it out.
Because of the popularity of ice fishing and the effort that must be exerted to make a hole through the ice there is a great need for a simple device for keeping ice holes from freezing over.
There is also a need for making holes and cavities in solidifying liquids and mixtures, such as concrete, or even when compacting dirt and such. Conventionally molds and forms are used, but these are generally fabricated at the site which takes up valuable time. An apparatus for creating standard sized holes in concrete, for example, and which could be reusable, or permanently left in for possible later removal, would be of great advantage to a builder or contractor. This ability to form holes or cavities of a desired size and depth in concrete, sand, soil, rubble or other construction materials would be advantageous. For example, the installation of street signs and posts can be simplified by making use of a standard sized cavity into which a complementary shaped post could fit, thus eliminating further labor and effort to secure it. Since a variety of different shapes and sizes of this invention are available, its use is limited only by imagination.
Other advantages and attributes of this invention will be readily discernable upon a reading of the text hereinafter.